81373337817 has 8 divisors (see below), whose sum is σ = 108508608000. Its totient is φ = 54243479760.

The previous prime is 81373337783. The next prime is 81373337819. The reversal of 81373337817 is 71873337318.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 81373337817 - 2⁸ = 81373337561 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 81373337817.

It is not an unprimeable number, because it can be changed into a prime (81373337819) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1317817 + ... + 1378182.

It is an arithmetic number, because the mean of its divisors is an integer number (13563576000).

Almost surely, 2^81373337817 is an apocalyptic number.

It is an amenable number.

81373337817 is a deficient number, since it is larger than the sum of its proper divisors (27135270183).

81373337817 is a wasteful number, since it uses less digits than its factorization.

81373337817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2706063.

The product of its digits is 1778112, while the sum is 51.

The spelling of 81373337817 in words is "eighty-one billion, three hundred seventy-three million, three hundred thirty-seven thousand, eight hundred seventeen".